1. Field of the Invention
The present invention relates to power-saving controllers for reducing power consumed when an image-forming apparatus stands by for image formation.
2. Description of the Related Art
There have been proposed a type of power-saving control in which a power-saving key for arbitrarily causing an image-forming apparatus to have a power-saving mode is pressed by a user so that the power-saving mode is activated, and another type of power-saving control in which no operation in a predetermined period automatically causes an image-forming apparatus to have a power-saving mode.
According to U.S. Pat. No. 5,681,493, when a power-saving mode is activated, a user can select a power-saving factor (the temperature of a fixing heater).
In U.S. Pat. No. 5,681,493, a selected low power-saving factor shortens a period needed for returning the temperature of a fixing heater to a temperature enabling image formation. However, there is a defect in that power saving is not effective when an image-forming apparatus is not used for a long time.
In other words, the function of selecting a power-saving factor by the user is not effectively used.